feat!: Refine lifecycle hooks; fix abortSignal

- add `stop` method. agent can be reused after stopped
- agent can not be reused after disposed
- extension DO NOT exposes `dispose` anymore. only `stop`.
- update panel for new `stop` method
- fix MultiPageAgent dispose event
- better handling abortSignal

packages/core/src/PageAgentCore.ts

@@ -68,6 +68,8 @@ export class PageAgentCore extends EventTarget {
 	taskId = ''
 	/** History events */
 	history: HistoricalEvent[] = []
+	/** Whether this agent has been disposed */
+	disposed = false
 
 	/**
 	 * Callback for when agent needs user input (ask_user tool)
@@ -183,7 +185,15 @@ export class PageAgentCore extends EventTarget {
 		this.#observations.push(content)
 	}
 
+	/** Stop the current task. Agent remains reusable. */
+	stop() {
+		this.pageController.cleanUpHighlights()
+		this.pageController.hideMask()
+		this.#abortController.abort()
+	}
+
 	async execute(task: string): Promise<ExecutionResult> {
+		if (this.disposed) throw new Error('PageAgent has been disposed. Create a new instance.')
 		if (!task) throw new Error('Task is required')
 		this.task = task
 		this.taskId = uid()
@@ -300,9 +310,13 @@ export class PageAgentCore extends EventTarget {
 				}
 			} catch (error: unknown) {
 				console.groupEnd() // to prevent nested groups
+				const isAbortError = (error as any)?.rawError?.name === 'AbortError'
+
 				console.error('Task failed', error)
-				const errorMessage = String(error)
+				const errorMessage = isAbortError ? 'Task stopped' : String(error)
 				this.#emitActivity({ type: 'error', message: errorMessage })
+				this.history.push({ type: 'error', message: errorMessage, rawResponse: error })
+				this.#emitHistoryChange()
 				this.#onDone(false)
 				const result: ExecutionResult = {
 					success: false,
@@ -315,10 +329,13 @@ export class PageAgentCore extends EventTarget {
 
 			step++
 			if (step > this.config.maxSteps) {
+				const errorMessage = 'Step count exceeded maximum limit'
+				this.history.push({ type: 'error', message: errorMessage })
+				this.#emitHistoryChange()
 				this.#onDone(false)
 				const result: ExecutionResult = {
 					success: false,
-					data: 'Step count exceeded maximum limit',
+					data: errorMessage,
 					history: this.history,
 				}
 				await onAfterTask?.(this, result)
@@ -601,6 +618,7 @@ export class PageAgentCore extends EventTarget {
 
 	dispose() {
 		console.log('Disposing PageAgent...')
+		this.disposed = true
 		this.pageController.dispose()
 		// this.history = []
 		this.#abortController.abort()

packages/extension/docs/extension_api.md

@@ -97,7 +97,7 @@ Parameters:
 
 Returns: `Promise<ExecutionResult>`
 
-#### `PAGE_AGENT_EXT.dispose()`
+#### `PAGE_AGENT_EXT.stop()`
 
 Stop the current task.
 
@@ -124,7 +124,6 @@ export interface ExecuteConfig {
   onStatusChange?: (status: AgentStatus) => void
   onActivity?: (activity: AgentActivity) => void
   onHistoryUpdate?: (history: HistoricalEvent[]) => void
-  onDispose?: () => void
 }
 
 export type Execute = (task: string, config: ExecuteConfig) => Promise<ExecutionResult>
@@ -189,7 +188,7 @@ const result = await window.PAGE_AGENT_EXT!.execute(
 ### Stop the Current Task
 
 ```typescript
-window.PAGE_AGENT_EXT!.dispose()
+window.PAGE_AGENT_EXT!.stop()
 ```
 
 ## Window Type Declaration
@@ -212,7 +211,6 @@ interface ExecuteConfig {
   onStatusChange?: (status: AgentStatus) => void
   onActivity?: (activity: AgentActivity) => void
   onHistoryUpdate?: (history: HistoricalEvent[]) => void
-  onDispose?: () => void
 }
 
 declare global {
@@ -221,7 +219,7 @@ declare global {
     PAGE_AGENT_EXT?: {
       version: string
       execute: Execute
-      dispose: () => void
+      stop: () => void
     }
   }
 }

packages/extension/docs/extension_api_zh.md

@@ -97,7 +97,7 @@ token 匹配后，插件会在 `window` 上注入 API。
 
 返回：`Promise<ExecutionResult>`
 
-#### `PAGE_AGENT_EXT.dispose()`
+#### `PAGE_AGENT_EXT.stop()`
 
 停止当前任务。
 
@@ -124,7 +124,6 @@ export interface ExecuteConfig {
   onStatusChange?: (status: AgentStatus) => void
   onActivity?: (activity: AgentActivity) => void
   onHistoryUpdate?: (history: HistoricalEvent[]) => void
-  onDispose?: () => void
 }
 
 export type Execute = (task: string, config: ExecuteConfig) => Promise<ExecutionResult>
@@ -189,7 +188,7 @@ const result = await window.PAGE_AGENT_EXT!.execute(
 ### 停止当前任务
 
 ```typescript
-window.PAGE_AGENT_EXT!.dispose()
+window.PAGE_AGENT_EXT!.stop()
 ```
 
 ## Window 类型声明
@@ -212,7 +211,6 @@ interface ExecuteConfig {
   onStatusChange?: (status: AgentStatus) => void
   onActivity?: (activity: AgentActivity) => void
   onHistoryUpdate?: (history: HistoricalEvent[]) => void
-  onDispose?: () => void
 }
 
 declare global {
@@ -221,7 +219,7 @@ declare global {
     PAGE_AGENT_EXT?: {
       version: string
       execute: Execute
-      dispose: () => void
+      stop: () => void
     }
   }
 }

packages/extension/src/agent/MultiPageAgent.ts

@@ -89,8 +89,7 @@ export class MultiPageAgent extends PageAgentCore {
 					isAgentRunning: false,
 				})
 
-				// no need to dispose tabsController and pageController
-				// as they do not keep references
+				tabsController.dispose()
 			},
 		})
 	}

packages/extension/src/agent/useAgent.ts

@@ -84,7 +84,7 @@ export function useAgent(): UseAgentResult {
 	}, [])
 
 	const stop = useCallback(() => {
-		agentRef.current?.dispose()
+		agentRef.current?.stop()
 	}, [])
 
 	const configure = useCallback(async (newConfig: LLMConfig) => {

packages/extension/src/entrypoints/content.ts

@@ -71,7 +71,8 @@ async function exposeAgentToPage() {
 				try {
 					const { task, config } = payload
 
-					// create when used
+					// Dispose old instance before creating new one
+					multiPageAgent?.dispose()
 
 					multiPageAgent = new MultiPageAgent(config)
 
@@ -116,17 +117,6 @@ async function exposeAgentToPage() {
 						)
 					})
 
-					multiPageAgent.addEventListener('dispose', () => {
-						window.postMessage(
-							{
-								channel: 'PAGE_AGENT_EXT_RESPONSE',
-								id,
-								action: 'dispose_event',
-							},
-							'*'
-						)
-					})
-
 					// result
 
 					const result = await multiPageAgent.execute(task)
@@ -155,9 +145,8 @@ async function exposeAgentToPage() {
 				break
 			}
 
-			case 'dispose': {
-				// @note stop ongoing processes but can still be re-used later
-				multiPageAgent?.dispose()
+			case 'stop': {
+				multiPageAgent?.stop()
 				break
 			}
 

packages/extension/src/entrypoints/main-world.ts

@@ -16,7 +16,6 @@ export interface ExecuteConfig {
 	onStatusChange?: (status: AgentStatus) => void
 	onActivity?: (activity: AgentActivity) => void
 	onHistoryUpdate?: (history: HistoricalEvent[]) => void
-	onDispose?: () => void
 }
 
 export default defineUnlistedScript(() => {
@@ -60,12 +59,6 @@ export default defineUnlistedScript(() => {
 					return
 				}
 
-				if (data.action === 'dispose_event' && config.onDispose) {
-					config.onDispose()
-					window.removeEventListener('message', handleMessage)
-					return
-				}
-
 				if (data.action !== 'execute_result') return
 
 				// execute_result
@@ -104,14 +97,14 @@ export default defineUnlistedScript(() => {
 		return promise
 	}
 
-	const dispose = () => {
+	const stop = () => {
 		const id = getId()
 
 		window.postMessage(
 			{
 				channel: 'PAGE_AGENT_EXT_REQUEST',
 				id,
-				action: 'dispose',
+				action: 'stop',
 			},
 			'*'
 		)
@@ -121,6 +114,6 @@ export default defineUnlistedScript(() => {
 	;(window as any).PAGE_AGENT_EXT = {
 		version: __EXT_VERSION__,
 		execute,
-		dispose,
+		stop,
 	}
 })

packages/llms/src/OpenAIClient.ts

@@ -54,8 +54,10 @@ export class OpenAIClient implements LLMClient {
 				signal: abortSignal,
 			})
 		} catch (error: unknown) {
-			console.error(error)
-			throw new InvokeError(InvokeErrorType.NETWORK_ERROR, 'Network request failed', error)
+			const isAbortError = (error as any)?.name === 'AbortError'
+			const errorMessage = isAbortError ? 'Network request aborted' : 'Network request failed'
+			if (!isAbortError) console.error(error)
+			throw new InvokeError(InvokeErrorType.NETWORK_ERROR, errorMessage, error)
 		}
 
 		// 3. Handle HTTP errors

packages/llms/src/errors.ts

@@ -34,12 +34,15 @@ export class InvokeError extends Error {
 		super(message)
 		this.name = 'InvokeError'
 		this.type = type
-		this.retryable = this.isRetryable(type)
+		this.retryable = this.isRetryable(type, rawError)
 		this.rawError = rawError
 		this.rawResponse = rawResponse
 	}
 
-	private isRetryable(type: InvokeErrorType): boolean {
+	private isRetryable(type: InvokeErrorType, rawError?: unknown): boolean {
+		const isAbortError = (rawError as any)?.name === 'AbortError'
+		if (isAbortError) return false
+
 		const retryableTypes: InvokeErrorType[] = [
 			InvokeErrorType.NETWORK_ERROR,
 			InvokeErrorType.RATE_LIMIT,

packages/ui/src/i18n/locales.ts

@@ -12,6 +12,7 @@ const enUS = {
 			question: 'Question: {{question}}',
 			waitingPlaceholder: 'Waiting for task to start...',
 			stop: 'Stop',
+			close: 'Close',
 			expand: 'Expand history',
 			collapse: 'Collapse history',
 			step: 'Step {{number}} · {{time}}{{duration}}',
@@ -59,6 +60,7 @@ const zhCN = {
 			question: '询问: {{question}}',
 			waitingPlaceholder: '等待任务开始...',
 			stop: '终止',
+			close: '关闭',
 			expand: '展开历史',
 			collapse: '收起历史',
 			step: '步骤 {{number}} · {{time}}{{duration}}',

packages/ui/src/panel/Panel.ts

@@ -33,7 +33,7 @@ export class Panel {
 	#statusText: HTMLElement
 	#historySection: HTMLElement
 	#expandButton: HTMLElement
-	#stopButton: HTMLElement
+	#actionButton: HTMLElement
 	#inputSection: HTMLElement
 	#taskInput: HTMLInputElement
 
@@ -76,7 +76,7 @@ export class Panel {
 		this.#statusText = this.#wrapper.querySelector(`.${styles.statusText}`)!
 		this.#historySection = this.#wrapper.querySelector(`.${styles.historySection}`)!
 		this.#expandButton = this.#wrapper.querySelector(`.${styles.expandButton}`)!
-		this.#stopButton = this.#wrapper.querySelector(`.${styles.stopButton}`)!
+		this.#actionButton = this.#wrapper.querySelector(`.${styles.stopButton}`)!
 		this.#inputSection = this.#wrapper.querySelector(`.${styles.inputSectionWrapper}`)!
 		this.#taskInput = this.#wrapper.querySelector(`.${styles.taskInput}`)!
 
@@ -105,6 +105,15 @@ export class Panel {
 			status === 'running' ? 'thinking' : status === 'idle' ? 'thinking' : status
 		this.#updateStatusIndicator(indicatorType)
 
+		// Morph action button: running = stop (■), not running = close (X)
+		if (status === 'running') {
+			this.#actionButton.textContent = '■'
+			this.#actionButton.title = this.#i18n.t('ui.panel.stop')
+		} else {
+			this.#actionButton.textContent = 'X'
+			this.#actionButton.title = this.#i18n.t('ui.panel.close')
+		}
+
 		// Show/hide based on status
 		if (status === 'running') {
 			this.show()
@@ -266,11 +275,15 @@ export class Panel {
 	}
 
 	/**
-	 * Stop Agent
+	 * Action button handler: stop when running, close (dispose) when idle
 	 */
-	#stopAgent(): void {
+	#handleActionButton(): void {
+		if (this.#agent.status === 'running') {
+			this.#agent.stop()
+		} else {
 			this.#agent.dispose()
 		}
+	}
 
 	/**
 	 * Submit task
@@ -383,7 +396,7 @@ export class Panel {
 					<button class="${styles.controlButton} ${styles.expandButton}" title="${this.#i18n.t('ui.panel.expand')}">
 						▼
 					</button>
-					<button class="${styles.controlButton} ${styles.stopButton}" title="${this.#i18n.t('ui.panel.stop')}">
+					<button class="${styles.controlButton} ${styles.stopButton}" title="${this.#i18n.t('ui.panel.close')}">
 						X
 					</button>
 				</div>
@@ -420,10 +433,10 @@ export class Panel {
 			this.#toggle()
 		})
 
-		// Stop button
-		this.#stopButton.addEventListener('click', (e) => {
+		// Action button (stop / close)
+		this.#actionButton.addEventListener('click', (e) => {
 			e.stopPropagation()
-			this.#stopAgent()
+			this.#handleActionButton()
 		})
 
 		// Submit on Enter key in input field

packages/ui/src/panel/types.ts

@@ -68,6 +68,9 @@ export interface PanelAgentAdapter extends EventTarget {
 	/** Execute a task */
 	execute(task: string): Promise<unknown>
 
-	/** Dispose the agent */
+	/** Stop the current task (agent remains reusable) */
+	stop(): void
+
+	/** Dispose the agent (terminal, cannot be reused) */
 	dispose(): void
 }

packages/website/src/pages/docs/features/chrome-extension/page.tsx

@@ -206,7 +206,6 @@ interface ExecuteConfig {
 	onStatusChange?: (status: AgentStatus) => void
 	onActivity?: (activity: AgentActivity) => void
 	onHistoryUpdate?: (history: HistoricalEvent[]) => void
-	onDispose?: () => void
 }
 
 type Execute = (task: string, config: ExecuteConfig) => Promise<ExecutionResult>
@@ -217,7 +216,7 @@ declare global {
 		PAGE_AGENT_EXT?: {
 			version: string
 			execute: Execute
-			dispose: () => void
+			stop: () => void
 		}
 	}
 }`
@@ -237,7 +236,6 @@ interface ExecuteConfig {
 	onStatusChange?: (status: AgentStatus) => void
 	onActivity?: (activity: AgentActivity) => void
 	onHistoryUpdate?: (history: HistoricalEvent[]) => void
-	onDispose?: () => void
 }
 
 type Execute = (task: string, config: ExecuteConfig) => Promise<ExecutionResult>
@@ -248,7 +246,7 @@ declare global {
 		PAGE_AGENT_EXT?: {
 			version: string
 			execute: Execute
-			dispose: () => void
+			stop: () => void
 		}
 	}
 }`
@@ -271,8 +269,7 @@ const result = await window.PAGE_AGENT_EXT.execute(
 		// includeInitialTab: false, // 设为 false 排除初始标签页
 		onStatusChange: status => console.log('状态变化:', status),
 		onActivity: activity => console.log('活动:', activity),
-		onHistoryUpdate: history => console.log('历史更新:', history),
-		onDispose: () => console.log('已停止')
+		onHistoryUpdate: history => console.log('历史更新:', history)
 	}
 )
 
@@ -287,8 +284,7 @@ const result = await window.PAGE_AGENT_EXT.execute(
 		// includeInitialTab: false, // Set to false to exclude initial tab
 		onStatusChange: status => console.log('Status change:', status),
 		onActivity: activity => console.log('Activity:', activity),
-		onHistoryUpdate: history => console.log('History update:', history),
-		onDispose: () => console.log('Disposed')
+		onHistoryUpdate: history => console.log('History update:', history)
 	}
 )
 
@@ -297,20 +293,18 @@ console.log(result) // Task execution result`
 						language="javascript"
 					/>
 
-					<h3 className="text-xl font-semibold mt-6 mb-3">PAGE_AGENT_EXT.dispose()</h3>
+					<h3 className="text-xl font-semibold mt-6 mb-3">PAGE_AGENT_EXT.stop()</h3>
 					<p className="text-gray-600 dark:text-gray-300 mb-4">
-						{isZh
-							? '停止当前正在运行的任务。停止后 Agent 可以重新使用。'
-							: 'Stop the current running task. The agent can be reused after disposal.'}
+						{isZh ? '停止当前正在运行的任务。' : 'Stop the current running task.'}
 					</p>
 
 					<CodeEditor
 						code={
 							isZh
 								? `// 停止当前任务
-window.PAGE_AGENT_EXT.dispose()`
+window.PAGE_AGENT_EXT.stop()`
 								: `// Stop current task execution
-window.PAGE_AGENT_EXT.dispose()`
+window.PAGE_AGENT_EXT.stop()`
 						}
 						language="javascript"
 					/>